Radiocarbon dating method synonyms

After pretreatment, samples for radiocarbon dating are prepared for use in an accelerator mass spectrometer by converting them into a solid graphite form.This is done by conversion to carbon dioxide with subsequent graphitization in the presence of a metal catalyst.Reference materials are also pressed on metal discs.

At this stage, other negatively charged atoms are unstable and cannot reach the detector.

The negatively charged carbon atoms, however, move on to the stripper (a gas or a metal foil) where they lose the electrons and emerge as the triple, positively charged carbon atoms.

At this stage, molecules that may be present are eliminated because they cannot exist in this triple charged state.

The carbon atoms with triple positive charge further accelerate away from the positive terminal and pass through another set of focusing devices where mass analysis occurs.

In mass analysis, a magnetic field is applied to these moving charged particles, which causes the particles to deflect from the path they are traveling.

If the charged particles have the same velocity but different masses, as in the case of the carbon isotopes, the heavier particles are deflected least.

From these data, concentration ratio of the isotopes can be known to allow evaluation of the level of fractionation.

The greatest advantage that AMS radiocarbon dating has over radiometric methods is small sample size.

Due to the sensitivity of accelerator mass spectrometers, carbon dating small particles like blood particles, a grain, or a seed have been made possible.

Accelerator mass spectrometry also takes less time to analyze samples for carbon 14 content compared to radiometric dating methods that can take one or two days.

Detectors at different angles of deflection then count the particles.

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